By exposing larvae of the holometabolous insect Spodoptera litura to the artificial diets supplemented with a range of Zinc (Zn) contents, we investigated Zn ingestion, excretion and accumulation in the insect throughout its life cycle. The effects of Zn stress on the survival, growth and food utilization of S. litura were also determined. Zn concentrations in the body (larvae, pupae, and adults), faeces, exuviates, puparium, eggs increased with the increasing Zn concentrations in the diets, while Zn excretion and accumulation by S. litura in 750 mg/kg Zn treatments was lower than the 600 mg/kg Zn treatment. In the 450 mg/kg Zn treatment, the Zn accumulation in S. litura at different developmental stages differed as follows: larvae > pupa > adult. S. litura ingested Zn via feeding and could excrete most of the Zn via faeces (compared with Zn excretion via exuviates) to reduce its internal Zn accumulation (compared with Zn ingestion). Survival and weight were significantly inhibited, and the prolonged period of development (larvae, pupae) and shortened longevity of adults were found in S. litura exposed to Zn stress greater than 450 mg Zn/kg. In the 150–450 mg/kg Zn treatments, the 6th instar larvae increased their relative consumption rate (RCR) and approximate digestibility (AD) (namely, food eaten) to gain weight, which resulted in greater Zn accumulation in the body. Therefore, below the threshold level (being close to 450 mg/kg Zn), S. litura seemed to have a strong homeostatic adjustment ability (increase the amount of food eaten, thereby increasing AD, RCR and Zn excretion via faeces and exuviates) to sustain their weight, and Zn was beneficial and harmless. Although larvae treated with 750 mg/kg Zn had a similar RCR and AD as the control, a reduced weight gain and prolonged larval period resulted in significantly lower relative growth rate (RGR), which indicated surviving insects may allocate more energy from foods for detoxification than for growth.

通过将全代谢昆虫斜纹夜蛾的幼虫暴露于补充一定范围的锌（Zn）含量的人工饮食中，我们研究了昆虫整个生命周期中锌的摄入，排泄和积累。还确定了锌胁迫对斜纹夜蛾存活，生长和食物利用的影响。日粮中锌的含量增加，体内（幼虫，p和成虫），粪便，粪便，，卵中的锌含量增加，而在750 mg / kg锌处理下，斜纹夜蛾对锌的排泄和积累低于600 mg / kg Zn处理。在450 mg / kg锌处理中，斜纹夜蛾中的锌积累在不同的发育阶段差异如下：幼虫>>>成虫。斜纹夜蛾通过进食摄取锌，并且可以通过粪便排泄大部分锌（与之相比，通过粪便排泄锌）可以减少其内部锌积累（与摄取锌相比）。暴露于锌胁迫下大于450 mg Zn / kg的斜纹夜蛾发现存活和体重受到显着抑制，并且发现长寿期（幼虫，p）和成年寿命缩短。在150-450 mg / kg的锌处理中，第六龄幼虫增加了相对消耗率（RCR）和近似消化率（AD）（即食用的食物）来增重，从而增加了体内锌的积累。因此，低于阈值水平（接近450 mg / kg Zn）时，斜纹夜蛾似乎具有很强的体内调节能力（增加食用的食物量，从而通过粪便和排泄物增加AD，RCR和Zn的排泄）来维持体重，而Zn有益而无害。尽管用750 mg / kg锌处理的幼虫具有与对照相似的RCR和AD，但体重增加减少和幼虫期延长导致相对生长速率（RGR）明显降低，这表明存活的昆虫可能会从食物中分配更多能量来排毒比增长。